The specific aims of this project are to investigate the determinants of race and ethnic-specific birth outcomes in the U.S. and the source of differences in these outcomes. The outcomes pertain to birthweight, low birthweight, neonatal mortality, and birthweight- and cause-specific postneonatal mortality. In some of our analyses, the race and ethnic groups to be considered include white non-Hispanics, black non-Hispanics, Puerto Ricans, other Hispanics, and Asians. In other parts of the research, we will focus on whites and blacks of all ethnic classes. Differences in these outcomes will be examined among couties, (a time series of cross sections for 1975-1986 with neonatal mortality and cause-specific postneonatal mortality for whites and blacks as the outcomes), states (the 1980 National Infant Mortality Surveillance with race-specific postneonatal mortality by birthweight and cause, by birthweight and mother's education, or by birthweight and mother's age as the outcomes), 1983 micro vital records on all induced abortions and live births in New York City and Tennessee (with birthweight and low birthweight for the five race/ethnic groups listed above for New York City and for whites and blacks in Tennessee as the outcomes), and monthly births in New York and Tennessee for 1968-1988 (with the percentage of light brains as the outcome). A unifying theme of the research is that a number of the determinants of infant health outcomes, including the decision to terminate a pregnancy, reflect choices made by pregnant women and their physicians. The specific aims will be accomplished via the estimation of multivariate statistical models. Some questions that we will address are: What are the effects of public programs on race- specific mortality? How sensitive is birthweight and cause- specific postneonatal mortality to physician availability, female poverty and income levels, and unemployment rates? What are the effects of variations in contraceptive costs and efficiency (factors that determine the "wantedness" of a birth) on birthweight as revealed by data that combine live births and abortions? What is the estimated impact of prenatal care in such data? Can the upward trend in the percentage of illegitimate births explain the modest decline in the percentage of light births in the face of a rapid increase over time in the prompt initiation of prenatal care, especially among minorities?